Real life benefits of carbon wheels?

[ripvanrando]

I recently rode cross country with carbon front rims and aluminum rims on the rear. TRP 957 brakes. Mfg required pads up front on the carbon rims with Kool Stops on the rear. I found that the front carbon rims braked better in the rain in the mountains. I wondered why. I wondered if the rims were so hot that the rain just sizzled off them.

[tuscanyswe]

Originally Posted by benb

He was talking about a 1000g weight difference in the wheels to get that 15w difference. What's the actual typical difference between high end alloy clinchers and most of the aero carbon offerings? It's not 1000g. If you go for the climbing specific super light carbon tubulars then you're losing some of the weight difference.

My regular all day open pro standard wheels with city rubber vs my corima 32s tubes currently on the bike is likely around 800g difference or so.

Im saying all cycling related is more or less placebo.
Im saying i feel a larger difference on light carbon rims in the city than i do the aero effect on open roads. The difference may be bigger on the open road where the aero effects take place but I'm not picking up on that while I'm riding to the same degree.
Im saying there is no need to worry about durability for riding carbon tubies or clinchers in the city if you have a nice reliable set up to begin with.

[ripvanrando]

True that the extra speed can't be felt.

I was shocked to bag a couple KOMs on segments that I had ridden scores of times. With good tires that are narrower than the rim by around 5%, there is a speed benefit. Won't help my sorry ass up Ventoux or Galibier any faster for sure.

[FlashUNC]

These threads really are the best.

[flydhest]

Isn't 10 seconds a long time to get to 20 mph?

[benb]

Originally Posted by tuscanyswe

My regular all day open pro standard wheels with city rubber vs my corima 32s tubes currently on the bike is likely around 800g difference or so.

Right maybe for your wheels. But there are alloy clinchers under $1000 that are within 200-300g of your Corimas and stuff at around $1100 that is closer to 150g difference.

Your corimas with 23s or 25s are probably 1000g lighter than the cheap Tiagra/Alex wheelset on my gravel bike with 38c file tread tires but that's a silly comparison.

[weisan]

Originally Posted by spartanKid

That's almost entirely placebo. The rotating weight thing is absolutely a myth.

Neglecting air resistance, for an 80 kg rider, accelerating from 10 mph to 20 mph in ten seconds, on a 2000 g wheelset vs a 1000 g wheelset, is a difference of 267 W vs 255 W.

This is of course neglecting air resistance.

Spartan pal, you are absolutely right.

[tuscanyswe]

Originally Posted by benb

Right maybe for your wheels. But there are alloy clinchers under $1000 that are within 200-300g of your Corimas and stuff at around $1100 that is closer to 150g difference.

Your corimas with 23s or 25s are probably 1000g lighter than the cheap Tiagra/Alex wheelset on my gravel bike with 38c file tread tires but that's a silly comparison.

I would think most ppl who ride in the city would have a similar wheelset as the one in my example. They weigh in close to 1800g. Campy hubs with open pros 32 spokes 3x. A very good and common wheelset. At least thats what most ppl around here ride in the city. Ad in skewers and heavier tires / tubes and the weight diff is there.

My corimas are really light but my point still stands.
I FEEL a larger difference in nice wheels in the city than i do on the open roads.
So to compare that to one of my carbon wheels dont seem to be silly at all from my point of view its pretty much exactly what the OP wanted opinions about the way i read his post.

[false_Aest]

Originally Posted by peanutgallery

If you like creaky wheels with a really limited lifespan, buy em. Otherwise save your dinero. Aero is the only benefit, plan on them lasting less than 5000 miles

I call bull****.

5000 miles means that I'm halfway through the lifespan of my new Boyds.
5000 miles means that on my highest-mileage years I'm going through 2.25 sets of wheels.
5000 miles means that clydesdales or those that do a lot of descending (this guy) would be out of a set of wheels even faster.

Creaking? BAH!

Hed, Bontrager, Reynolds, 2 sets of Boyds and Enve/Edge. I have yet to have a creak emanate from any CF hoops I've ridden. Bad quick releases, not lubing the skewer, improperly clamping the wheel in, valve rattling -- yeah. That's not the fault of the hoop though.

[drewskey]

Originally Posted by benc

200+\- miles a week of shotty intown Atlanta roads.

Brave soul right here riding in Atlanta.

[vqdriver]

wow. thought it was a simple question, just wanted to know what to expect from these when i satisfy the curiosity and buy a set.
i assumed that carbon wheels are established enough that they weren't so polarizing anymore.

let's focus on the braking then. all the other stuff, weight, "speed", sound, i can decide for myself if it's for me, but the braking is a function that just absolutely needs to be there. are we at the point that standard rim brakes (with whatever recommended pads) will work reasonably well? riding in populated areas, there can be lots of surprises some days.

[FlashUNC]

Originally Posted by vqdriver

wow. thought it was a simple question, just wanted to know what to expect from these when i satisfy the curiosity and buy a set.
i assumed that carbon wheels are established enough that they weren't so polarizing anymore.

let's focus on the braking then. all the other stuff, weight, "speed", sound, i can decide for myself if it's for me, but the braking is a function that just absolutely needs to be there. are we at the point that standard rim brakes (with whatever recommended pads) will work reasonably well? riding in populated areas, there can be lots of surprises some days.

Fwiw, my Hyperons brake slightly worse than my Shamals, but it ain't by much. Still on par with a lot of alloy rims I've ridden, and that's down some rather funky descents here in the East Bay.

[tuscanyswe]

Many carbon rims still struggle when wet. In dry breaking is a non issue on carbon rims imo

[Hermes_Alex]

Yeah, braking when it's wet is something that has been improved upon but still isnt great - I get the impression that the proportion of people who actually ride in the rain is smaller than is supposed. In normal conditions, most don't bite quite as strongly as aluminum, but the power on tap is totally adequate, especially with newer models.

[carpediemracing]

Originally Posted by vqdriver

let's focus on the braking then. all the other stuff, weight, "speed", sound, i can decide for myself if it's for me, but the braking is a function that just absolutely needs to be there. are we at the point that standard rim brakes (with whatever recommended pads) will work reasonably well? riding in populated areas, there can be lots of surprises some days.

I didn't weigh in on the previous stuff.

For braking the carbon rims I've used in the rain (Reynolds DV46 and Stinger 6) have been fine. There's an initial moment of nothing and then a lot of braking power. In fact when I was on aluminum rims I had two 100% panic moments on steep downhills in the rain where I was 100% on the brake levers and the bike wasn't slowing. It wasn't accelerating, it just wasn't slowing. Like being in a car sliding 5 mph on ice.

With carbon rims I'd drag the front brake regularly in the wet to keep them sort of primed if you will. I avoided using the rear brake because usually I was in a race and I didn't want people behind me to think I was braking.

My car used to be like that also. It had big brakes, aluminum center "hat" with steel rotors, grooved and cross drilled. They cooled down really well, I could brake really hard multiple times from higher speeds without any problems. Problem was that the rotors cooled too well in regular use. In the wet or in the cold I actually manually dragged the brakes when I could (so I'd lightly ride the brakes if it was clear behind me). In the rain the brake dragging made a huge difference, it would take maybe half a second of pressure before the brakes started to bite, with the "brake dragging" it would bite right away.

Koolstop salmon pads on carbon.

I don't even change pads between aluminum and carbon, haven't since 2010 or so. In 2008-2009 I had carbon clinchers and tubulars so no pad changes anyway, and before that I didn't change pads, was using carbon brake track tubulars since 1995? whenever Zipp 340s/440s came out.